Elevator control device

Abstract

When there is a breakdown in either one of first and second power converters supplying electrical power to a multi-winding motor comprising a wind-up mechanism, a rescue operation can be safely and reliably carried out by using the remaining power converter. A wind-up mechanism comprises a two-winding motor having first and second windings, and, during normal operation, power is supplied to the first and second windings from first and second inverters respectively. When the first inverter has broken down due to excessive current, first and second contactors are switched off, and a third contactor comprising a short-circuiting unit is switched on. Consequently, both windings receive power from the second inverter, enabling the rescue operation to be carried out without causing vibrations.

1. An elevator control device comprising:
 a wind-up mechanism, comprising a multi-winding motor having first and second windings provided on either side of a sheave; 
 first and second power converters which supply power to the first and second windings respectively; 
 a short-circuiting unit which short-circuits the output sides of the first and second power converters; and 
 a control unit which, when one of the first and second power converters has broken down, stops the operation of the broken-down power converter, allows the short-circuiting unit to perform a short-circuit operation, and allows a rescue operation to be carried out to the wind-up mechanism by supplying power from the other power converter to the first and second windings. 
 
   
   
     2. The elevator control device as described in  claim 1 , wherein
 input sides and output sides of the first and second power converters are connected to power, and to the first and second windings, via input side contactors and output side contactors respectively; and 
 the control unit allows the short-circuiting unit to perform a short-circuit operation only in the case where the control unit has input an off-operation answer-back signal which shows that the input side contactor and the output side contactor, connected to the broken-down power converter, have switched off, and has input an on-operation answer-back signal which shows that the input side contactor and the output side contactor, connected to the healthy power converter, are switched on. 
 
   
   
     3. The elevator control device as described in  claim 1 , wherein, when executing the rescue operation to the wind-up mechanism by supplying power to the first and second windings from the other power converter, the control unit gives the acceleration and deceleration speeds predetermined values which are lower than those during normal operation. 
   
   
     4. The elevator control device as described in  claim 1 , wherein the control unit inputs a carriage internal load detection value, and, when the load detection value is within a set range, sets the acceleration speed and, where necessary, the deceleration speed, to a first set value; when the load detection value is outside the set range, the control unit sets the acceleration speed and, where necessary, the deceleration speed, to a second set value which is smaller than the first set value. 
   
   
     5. The elevator control device as described in  claim 4 , wherein, when the load detection value is outside the set range, the control unit terminates the execution of the rescue operation instead of setting the acceleration speed and, where necessary, the deceleration speed, to the second set value.